If you have a big chest going down to touch the chest is a small movement, usually arm is bent 90 degree. If your chest is not so big, the movement is a lot bigger and shoulder pressure is a lot more. You will need to let the elbow goes well below shoulder level to touch the chest. Big chest man touches the chest with ease (do big chest). Others peoples with smaller chest dimensions need to torture the shoulder by placing elbow below shoulder level to touch the chest.